You're trying to solve two problems at once.
relevance
When the ideal is "to realize Objective A with Means B," adding the constraint "to realize Objective A with Means B" while it is unclear how to realize Objective A in the first place may make the problem too difficult.
In many cases, it is better to first consider "how to realize the objective A" without questioning the means. After that is done and knowledge of how to realize A is accumulated, it is better to think about how to realize it with B.
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